Subsurface electrodes for electric field shaping with wrapping supporting structures

ABSTRACT

An electric stimulator for heart (as in heart pacemakers), brain (as in DBS), organs and general cells, with a supporting structure where there exists a plurality of electrically isolated electrodes called passive electrodes or field-shaping electrodes that are located under the surface of the supporting structure. The passive electrodes are controlled by an appropriate electronics control unit and powered by some electric energy storage, as a battery. Passive or field-shaping electrodes are electrically insulated, being unable to inject current in the surrounding medium, but they are capable of shaping the electric field in the space surrounding the electrodes, which has consequence on the path of the stimulating currents injected by other devices or by the organism itself. The invention also discloses locating the passive electrodes on surfaces that surround the desired target volume.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority to the innovative U.S.Provisional Patent Application No. 62/114,038, filing date 2015 Feb. 9.

This patent application is a continuation-in-part of the brilliantpatent application Ser. No. 15/019,969, filing date 2016 Feb. 9,currently allowed, of the same inventor as this one.

This patent application is related to U.S. patent application Ser. No.13/470,275, to US Provisional Patent Application No. 61/881,997 dated2013 Sep. 25 to US Provisional Patent Application No. 61/027,116 dated2014 Jul. 21, to U.S. patent publication number 2010/0082076, to U.S.patent publication number 2010/0079156, to U.S. patent application Ser.No. 13/053,137, dated Mar. 21, 2011 entitled “Method and means toaddress and make use of multiple electrodes for measurements andelectrical stimulation in neurons and other cells including brain andheart” by Chong Il Lee and Sergio Lara Pereira Monteiro, which all ofwhich are incorporated herein by reference in their entirety.

FEDERALLY SPONSORED RESEARCH

Not applicable

SEQUENCE LISTING OR PROGRAM

Not applicable

BACKGROUND OF THE INVENTION Field of Invention

This invention relates to electrical stimulation of cells in animals andother living forms, particularly to electrical stimulation of heartcells, including heart muscles associated with heart muscle contractionand purkinje and similar fibers, and more precisely, it relates to theart of causing an efficient contraction sequence of the heart muscle inorder to maximize the volume of blood pumped per unit of energy spent bythe heart, known in medicine as the pumping fraction. It also relates tothe art of electrical stimulation of the cochlea, as in cochlearimplants. It also relates to the art of electrical stimulation ofneurons as in brain and peripheral neurons. Brain neurons are stimulatedboth for clinical objectives, as in Parkinson's disease control, and inanimal research as well, in which case neurons are stimulated to observethe consequences of the stimulation. It also relates to the art ofelectrical stimulation of organs, as stomach, to control appetite inheavy persons, as in afferent neurons, to control pain in painfulpersons, etc.

Discussion of Prior Art

In line with the patent requirement of being precise on the descriptionof the device and of the method of the invention we start with adefinition of the key concepts used in this patent document.

Field-Shaping Electrode (E-Field Electrode).

Also called by us as “passive electrode” and Type-2 electrodes. Theseare the electrodes that are covered by an electric insulating layer,being therefore unable to inject electric charges on the environmentsurrounding the device. They are, nevertheless, well capable to projectan electric field in the surrounding tissues (if inside an animal) orany other environment, for the same principle that a wooden or concretefloor prevent objects from moving down but does not prevent thegravitational field from acting beyond it. A floor is a gravitationalinsulator as much as glass and rubber are electrical insulators.

Passive Electrode.

Also Field-shaping electrodes (q.v.). These are electrically insulatingelectrodes, which are capable of projecting an electric field in theirsurroundings but, being covered by an electrically insulating layer areincapable of injecting any electric charges in their surroundings. Thepassive electrodes are for electric charges are what a floor is forgravitational force: a wooden or concrete floor prevents mass frommoving through them, as much as a glass or rubber cover on an electrodecauses that no electric charge can move through them. But thegravitational field, in one case, and the electric field, on the othercase, can penetrate the insulating barrier—rigid floor in one case,glass or rubber, etc. in the other case.

Subsurface Electrode (Also Underground Electrode Also SubterraneanElectrode).

These are our names for insulated electrodes that are under the outersurface of the electrode supporting structure Supp (picafina, cordum,etc.) of our invention and, therefore, under any active stimulatingelectrodes that may inject electric charges in the surroundingenvironment. Keeping in mind that the underground electrodes arenecessarily passive electrodes, electrically insulated, they incapableof injecting any electric charge in the surrounding tissues, yetperfectly capable of projecting an electric field in the environmentsurrounding the supporting structure, inclusive having a strong effecton a stimulating electrode located right above it, if there are anyabove it. The effect of an underground electrode on a stimulatingelectrode right above is is larger because the separation being smaller,the force caused by the electric field created by the undergroundelectrode is stronger than it would be if the underground electrode wereat a more distant location, just by the 1/r̂2 type of functionality ofCoulomb's law (and electric field too).

This patent relies on knowledge that are part of two disjoint fields ofknowledge: medicine and physics/electrical engineering (EE), moreparticularly electrophysiology and the theory of electric fields.Because of this we are forced to review concepts that are ratherelementary to both fields, considered trivial to one field but not knowat all to the other field. We do so in hope to make our invention clearto all readers, that is, to both medical people and to physicists/EE aswell.

The heart is divided into four chambers: left and right atria, at theupper part of the heart, and left and right ventricles, at the lowerpart of the heart. Right and left are arbitrarily assigned to be fromthe point of view of the person—which is the opposite left-right fromthe point of view of the observer looking at the person from the front.The atria are more holding chambers then actually pumping devices,evolved to quickly fill up the ventricles, below them, and consequentlytheir walls are thinner when compared with the lower part, theventricles. The right heart is responsible for the pulmonarycirculation, receiving venous (non- or little-oxygenated) blood from thefull body at the right atrium, passing it down to the right ventriclebelow it, from where the blood is pumped to the lungs. This correspondsto a short path, to the lungs and back. Back from the lungs, the bloodenters the left atrium, which holds some oxygenated blood volume thenreleases it down to the left ventricle below it, from where the blood isthen pumped to the whole body. The left heart pumps blood to the wholebody, which involves more work when compared with the shorter path fromthe right heart to lungs and back, so the left atrium has thicker,stronger walls. These considerations on the wall thickness are ofimportance on our invention, because our invention deals with theoptimization of the pumping mechanism of the heart, which is heavilydependent on the propagation delays of the electrical pulses that causesthe pumping mechanism, as explained below.

The electrical nature of muscle contraction was first observed in thewaning years of the 1700s by Luigi Galvani, who noticed that a frog'sleg contracted when subjected to an electric current. Today it is knownthat all our muscles, from a blinking eye or a walking leg, to themoving fingers of the inventor typing these words, work on the sameprinciples observed by Galvani—including our hearts. The heart contractsas response to an electric pulse, which is injected on it at therequired frequency, which varies according to the person's activity andstate of excitation. It is crucial here to keep in mind that thiselectric pulse does not propagate as the ordinary power in copper wires,which occurs very fast, virtually instantaneously from the human pointof view, but propagates rather as a displacement of heavy ions insideand outside of the muscle cells, subjected to much scattering and otherobstacles. In fact, the time elapsed between the initial contraction ofthe atrium, or upper heart chamber, and the ventricle, or lower heartchamber, is of the order of 120 to 200 ms—a rather long time forelectronics events (long enough for an electric pulse on a power line togo completely around the earth. Of course that 120 ms, which isapproximately 1/10 of a second, is still instantaneous from the point ofview of human perception. It is, nevertheless, so much longer than thetimes in which electronics work that it lends itself to easymanipulation by implanted artificial electrodes. This slow propagationof the electrical pulse in the heart muscle is important for the workingof our invention, so the reader is requested to keep this fact in mind,that the propagation times of the ions that cause the muscle contractionis very long—a very slow contraction sequence.

Several malfunctions are possible to occur that hinder the properfunctioning of the heart. Some are of a mechanical nature, a subject notbearing on our invention, while some are of an electrical nature, whichis the focus of our invention, as described later on: our invention isan inventive method and means to cause a better propagation of theelectric pulse that causes the heart to beat—and consequently, ourinvention is an inventive method and system to cause a better heartpumping.

Given that a proper understanding of the mechanism of heart beating andof the propagation of the electrical pulse that determines it is crucialto the understanding of our invention, we proceed to a brief explanationof the mechanism of the heart beating. This is also necessary because,as written above, our invention is based on two separated and insulatedfields of knowledge: medicine & physiology and physics & electricalengineering, which are separately well understood by two groups ofpersons, but hardly by the same individual.

There are a wealth of books on the subject, as Thaler (2003), where thereader with a non-medical background can get more detailed information.In short, most muscles capable of contracting are made of such cellsthat under normal conditions they have an excess of negative ions insidetheir cellular walls, which causes an excess of positive ions justoutside their cellular walls, attracted there by ordinary electrostaticattraction. When in this condition, its normal condition, the cell issaid to be polarized (medical terminology, not the same as physics/EE,it confused me a lot in the beginning). If the cell loses its innernegativity, the language of electrophysiology describes this as adepolarization event. We here warn the reader that from the point ofview of a physicist/EE this is a poor choice of name, because the cellis still polarized when the electrophysiologists mention adepolarization event, but it becomes polarized on the opposite direction(positive inside it). By a sequence of well-know mechanism thisacquisition of positive charges (depolarization as said in the medicaltrade, misnomer as it is) causes the cell to contract, that is, todecrease its length. This is the mechanism behind the blinking of oureyes to show develishness, behind our leg motion to run from the forcesof repression in student or general 99% demonstration—and also behindthe heart contraction. It being an electric phenomenon, this event canbe controlled by the injection of the appropriate electrical pulse inthe heart muscle. This will be described in the sequel, and ourinvention bears on a twist on the man-made mechanism (heart pacemaker)designed to cause a heart pumping contraction sequence. Our inventionimproves on the propagation of the artificial electric pulse that causesa heart contraction (and consequent blood pumping).

As a last preparation information we want to clarify that the heartpumping mechanism is a modification of a class of pumps calledperistaltic pump, which causes the motion of the fluid, or pumping, witha progressive forward squeezing of the container, which forces the fluidforward. If the reader is unfamiliar with the mechanism of peristalticpumping, we recommend that he/she acquaints him/herself with the method,perhaps observing the animation in today's wikipedia article onperistaltic pump, or any similar source. The reader is requested to keepthis fact in mind as he reads the explanation of our invention, that thehearts functions with a progressive squeezing of its chambers, akin tothe milking of a caw, during which process the milker progressivelysqueezes the caw's fit between its pointing finger and the thumb, thenpress the middle finger, squeezing the stored liquid further down fromthe tit, then the annular than the little finger, at which point all thecan be squeezed is out, the hand is opened to allow more milk to enterthe tit from the top and the process is repeated.

The reader must be warned too that though every cardiologist will alwaysstate that the heart pumps sequentially, many a cardiologist that statesthis mean only that the atrium contracts first, then the ventriclecontracts after, then repeat the same cycle, unaware that within each ofthe two cycles the actual contractions is sequential in the sense thatthe muscles start contracting at one extremity (say, the top of theatrium) then sequentially contracting down, toward the exit valve at thebottom. This latter sequence is the one the inventor wants to bringforth—and a sequence that, alas, many a cardiologist will deny. FIGS.9A, 9B, 9C and 9D show a cycle of the ventricle contracting from thebottom to the top, which is the necessary direction because the exit forthe ventricles is at the top of the ventricle.

In short, most of the heart cells are part of the miocardium, which is avariety of a large group of other cells which are capable of contractingwhen subjected to the mechanism just described of depolarization. Thepumping sequence consists of blood entering the heart at the top of theatrium (which is also the upper chamber), then a sequential downwardpumping squeeze of the atrium which squeezes the blood into the lowerventricle. Then there is a problem because the exit of the ventricles isat its upper part, next to the entrance port from the atrium, so, if thesqueezing continued downward there would be no place for the blood to go(no exit port at the bottom of the ventricle!). This problem is solvedwith the interruption of the downward propagating electric pulse at theintersection of these two chambers and a re-emission of another pulsethrough fast channels known as His fibers, left and right bundles andfinally the Purkinjie fibers which release the electrical pulse at thebase of the ventricle, which then begin squeezing from bottom to top,squeezing the blood upwards towards the exit port (the pulmonary vein atthe right ventricle and the aorta at the left ventricle).

So, the heart's electrical system starts with an electrical pulse at thetop of the right atrium, from a small group of cells known as thesino-atrial node (SA node or SAN), as seen in FIG. 1, from where itpropagates fast to the left atrium by special fibers that propagate theelectric pulse better than the miocardium muscle does, which causes adownward contraction of the atrium, the right atrium first, then theleft atrium with a minimal delay with respect to the right atrium. Theelectric pulse, which has been propagating downwards is then captured atthe base of the atrium, preventing it from continuing down, it is thenused by special cells called the atrial-ventricular node (AV node orAVN) (FIG. 1) to start a new pulse which is send through specialconduits (special wires, so to say), known as the His bundle, then theright and left bundle branch, then the Purkinjie fibers, which thenrelease the electrical pulse regenerated at the atrio-ventricular nodeAVN at the lower part of the ventricles, causing now the ventricle tostart contracting upwards, as needed to pump the blood to the upper exitport of the ventricles. This completes the heart cycle. Such a ventriclecontraction is shown schematically at FIGS. 9 (A, B, C and D).

Electrical malfunctions of the heart may be more obvious faults asinsufficient energy in the electrical pulse that causes the pumping orsome more subtle ones as errors in the propagation of the electricalpulse. Our invention inserts itself in this latter category, it being adevice to control the propagation of the electrical pulse through theheart muscles, therefore to control the sequential contraction of theheart muscle in the broader sense we use the concept here, that is, thecontinuously progressive contraction of the heart muscle, cell-to-cell,from the blood entry port to the blood exit port. The originalartificial heart pacemakers simply injected an electric pulse near thesino-atrial node SAN at the top of the right atrium (FIG. 1), and laterversions injected two or even three separate pulses in two or threedifferent parts of the hearts, with the appropriate time delays, whichcorrespond to the elapsed time for the natural pulse to be at that placefor a good contraction sequence. This multiple electrode stimulation isknown in the medical field under the name of resynchronization therapy,and an example of it with two electrodes electr1 and electr2 is shown atFIG. 2. None of the existing devices, though, even attempted to controlthe path of the injected current once it is injected artificially—whichis the object of our invention. In other words, our invention improveson the electrical propagation features of the electric pulse created bythe artificial heart pacemakers, and in doing so it improves thesqueezing sequence of the heart, which in turn improves the pumpingefficiency. It is to be remembered that, because the heart is avariation of a peristaltic pump, the pumping sequence is of fundamentalimportance for an efficient pumping (the inventors hope that the readerdid indeed go see the animation in Wikipedia). We also remind the readerthat earlier patent of the same inventors describe simpler versions ofthis invention disclosed in this document.

Originally heart pacemakers were simply an exposed wire wire tip, thewire connected to a battery and electronics circuitry to create pulsesof appropriate frequency, shape and amplitude. The original implant wasmade with an open chest surgery, but this was quickly supplanted by aless invasive and much less traumatic technique, with which an incisionwas made on some vein at the chest (usually the subclavian vein, on theupper chest), where a wire was inserted, which had some sort of screwingor anchoring ending at its distal extremity, then this wire was fed inuntil its distal extremity reached the upper right heart chamber, fromthe inside (the right atrium), where the wire tip was screwed on theinner part of the heart, near the natural starting point of theelectrical pulse that causes the heart to beat, know as the sino-atrialnode (SA node or SAN), as seen in FIG. 1. During this process thepatient is in an X-ray imaging system and the surgeon can observe theadvancement of the wire down the vein on an X-ray monitor. The proximalend of the wire was then connected to a battery and electronics boxwhich was implanted in the chest, in some convenient location. From thewire tip anchored at the distal end, a current emanated, which thenpropagated through the heart muscle, causing the muscle to contract asthe current proceeded along it, hopefully similarly to the naturallyoccurring electric pulse. It is crucial here to remember that thismuscle contraction occurs because of the electric charge carried by it,and consequently, it is the electric current propagation time andpathway that determines the heart contraction sequence—because themuscle cells contract as a consequence of the electric charge near it.The sequence of muscle contraction is crucial for an efficient heartfunctioning, because the heart must start squeezing from its furthestend, away from the discharge exit area, most away from the exit port,continuously squeezing its wall towards the exit port. The heart doesnot contracts as a person squeezes a tennis ball for exercise, butrather, the heart squeezes sequentially pushing the blood forward,towards the exit port. The reader can here recall the caw milkingdescribed above. Most people get astonished when they learn that theheart pumps not much more than 50% of the blood in it (approximately 70%for a healthy young person)—a rather low efficiency! So much for theAmerican intelligent design: intelligent he was not.

Over the more than 50 years of heart pacemaking, many types of electrodetips have been developed. Some of the electrode tips possessed somedegree of symmetry, some not. Whether or not the tip electrode had ornot symmetry, this quality was transferred to the current injected intothe heart muscle. The heart, on the other hand, is asymmetric,particularly from the point of view of the point where the stimulatingelectrode is anchored in the heart, which often is near the sino-atrialnode, or at the top of the right atrium. It follows that the currentthat is injected by current art heart pacemakers cannot follow well thecontour of the heart muscle, causing a less than ideal contractingsequence. Other anchoring positions for the electrode are also used, andmultiple electrodes as well, which may stimulate the atrium and theventricle independently, a method much used today and known asresynchronization therapy, shown in FIG. 2.

In the former case, the tip symmetry had consequences on the currentdistribution in the heart muscle, because, at least initially, it causeda current symmetry. In the latter case, the lack of symmetry also hadconsequences on the current distribution, because it caused an initialasymmetric current injection, which could or could not be the ideal forthe heart contraction sequence. In either case, the trajectory ofcurrent injection has not been controlled by prior art devices, whichwas a major problem as acknowledged by cardiologists working in thefield of electrophysiology. This lack of control of the currentdistribution, as it propagated through the heart muscle, plagued all theearlier art of heart pacemakers, and still does in current art.Throughout the years, many variations were introduced in the electrodes,as the shape of the wire tip, which served to anchor it in place, butthese changes were largely for mechanical reasons, as to provide a moresecure anchoring of the electrode on the heart muscle, or to minimizephysical damage to the heart tissues, etc. Changes have also occurred onthe method of introducing it in the heart, but most of these werechanges to solve other problems, not to induce a good squeezing sequenceof the heart muscle. Consequently, the uncontrolled propagation of theelectric current from the tip has been a constant. Attempts to improvethe electric pulse propagation include the use of multiple wire tips,which injected current not only at different locations but also atdifferent times, or with relative time delay between the stimulatingplaces. Examples of such multiple site stimulation are atrial andventricular stimulators, two tips, one at the atrium, another at theventricle, which deliver a pulse with a time lag between them,corresponding to the time lag between atrial contraction and ventricularcontraction. But these multiple stimulating tips are not designed tocontrol the electric field—which determines the path of the injectedelectric current, which more or less follows the electric field linesbecause these are the force lines.

Another interesting way to look at the multiple stimulating electrodesused in resynchronization therapy is that all the multiple electrodes dois to start the process over again at half-way through the cycle, whichis done exactly because it is widely recognized that the propagation ofthe causative electric pulse is often messed up as early as half-waythroughout the sequence! This starting over, a kind of marriage therapyof the heart's contracting muscles, is less than what is desirable, andcan be made better with a positive control through the electric pulsepropagation process—which is the objective of the device disclosed inthis patent application document.

Such multiple electrodes used in resynchronization therapy, usually,though not consistently, worked better than a single electrode. Yet,this lack of optimization of the heart muscle contraction has been amajor problem known to the practitioners of the art. This uncontrolledpropagation was shared by most, if not all models and their variations,in spite of the fact that the cardiologists were aware that uncontrolledelectric pulse propagation caused inefficient heart pumping.Cardiologists knew that they had to address the problem of electricpulse propagation through the heart, but they have so far not succeededin this goal. It has been a known problem in heart pacemakers, yet andamazingly, a problem which has defied solution for decades.

Moreover, even if multiple stimulating tips caused an improvement of thepumping squeezing sequence and efficiency, it had the detrimental effectof causing more muscle damage, as each anchored wire tip is a foreignbody in the heart, also a foreign body which by necessity caused aninjure to it, an injury which resulted in a scar tissue, which in turnhas different electrical conductivity when compared with the normalheart, creating a problem spot for the very objective of controlledelectric pulse propagation. Another problem was that, since often timesthe first attempt to anchor the tip in the endocardio is unsuccessful,either for mechanical or for electrical reasons, for every unsuccessfulattempt the surgeon has to retract the tip then screw it again somewhereelse, and occasionally even more than two attempts, each tip wereusually responsible for multiple scars in the inner heart, which in turnposed limits to any dream of using a multiplicity of stimulating tips.

It seems that all prior art attempted to solve the problem of electricpulse propagation inside the heart muscle tissues with the use ofmultiple electrodes, while nobody succeeded to control the currentpropagation, in direction and magnitude, using one single electrode. Norhave prior art made full use of multiple electrodes to more completelyshape the electric field within the heart muscle—which is the same asthe electrical current path, because the electric field lines are thesame as the force lines, or the lines along which the injected chargesmove.

Prior art simply used an arbitrarily shaped stimulating electrode, whichthan created a non-controled electric field in the surrounding space,which in turn guided the injected charges (or electric current). Ourinvention offers a method and a means to adjust the electric field,independently from the stimulating electrodes, to the best shapedepending on the particular case, as needed.

Several authors have discussed the problem of guiding the electriccharge injected in animal tissue for electrical stimulation [e.g.,Butson and McIntyre “Current steering to control the volume of tissueactivated during deep brain stimulation”, Brain stimulation V.1, pg.7-15 (2008), Butson and McIntyre “Role of electrode design on the volumeof tissue activated during deep brain stimulation” J. Neural Eng. V3 pg1-8 (2006), Julia Buhlmann et al. “Modeling of a segmented electrode fordesynchronizing deep brain stimulation” Frontier in Neuroeng. V 4,article 15 (December 2011)]. These and others propose to take advantageof the electric field created by the stimulating electrodes to “guide”the electric charges injected by the same electrodes. An vivid analogyof the situation is the motion of the water along any river, whichfollows the channels that are directed to the ocean. In the case of therivers the water is following the lines of the gravitational potentialcreated by the planed earth underneath the path, while in the case ofbody cells electric stimulation the electric charges have to follow theelectric potential created by any other electric charge that existaround the space in question. Of course that the stimulating electrodesby necessity create an electric field in the space surrounding them,which, in turn, cause a force on the electric charges injected by them,thereby applying a force, that is, guiding the path of the injectedcharges. What all the workers have so far failed to notice is that aslong as they use the same electrodes for injecting charges and forelectric field shaping they run into a brick wall because the chargeinjecting electrodes are on for a very very short time (a very smallduty cycle), which typically may be 2% for DBS as used for Parkinson'sDisease control or even <<1% for artificial heart pacemaking. Once onetakes notice of this, it follows that a solution for the goal of guidingthe charges AFTER they have been injecting have to rely on electrodesthat do not inject charges into the system. A solution to this conundrumwas offered by the inventor and co-inventors, as described in U.S. Pat.No. 8,954,145, Feb. 10, 2015, where we disclosed a second type ofelectrode, which we called then PASSIVE ELECTRODE, sometimes referred byus as field-shaping electrode. As defined by us, passiveelectrodes/E-field electrodes are electrodes that are unable to injectelectric charges because they are covered by an electrically insulatinglayer.

Patent application Ser. No. 15/019,969 (currently allowed, not yetissued, will issue November 2018) disclosed an improvement on the devicedisclosed in U.S. Pat. No. 8,954,145. Patent Ser. No. 15/019,969discloses electrodes under the surface of the supporting structure Supp,which allows for more space for both the active electrodes and thepassive electrodes as well. In this current patent application wedisclose a further improvement on the E-electrodes/passive electrodes,consisting of a device and a method of enveloping or partly envelopingthe target organ in a surface populated with the E-electrodes thatcontrol the current path as the ions move through the target volume. Theguiding principle for this is that with more passive electrodes atdifferent positions around the target volume, it is possible to bettercontrol the E-field in the target volume—there are more options, andtherefore to better control the position, in space and time, of thepropagating ions, because the E-field is the origin of the force on theions.

OBJECTS AND ADVANTAGES

Accordingly, several objects and advantages of our invention are one ormore of the following. A better squeezing sequence of the heart muscle,starting the muscle contraction from the distal end of the heart furtheraway from the exit port, to the proximal end of the heart closer to theexit port, with view to achieve a more efficient pumping, when comparedwith prior art heart pacemakers which were designed with no view tooptimize the squeezing sequence.

Another object and advantage of our invention is to offer the ability toinject an electric current in the heart which causes a higher pumpingfraction, or the fraction of the blood which is actually pumped out ofit, or out of each chamber, when compared with prior art artificialpacemakers.

Another object and advantage of our invention is to adjust the electricfield over the heart muscle to take better advantage of the atrialventricular node to cause a better squeezing sequence of the heartmuscle when compared with prior art artificial pacemakers.

Another object and advantage of our invention is to adjust the electricfield over the part of the heart muscle where the His bundle and theright and left bundles are, to control the propagation times of theelectric current coming from the atrial-ventricular node to the bottomand sides of the ventricle, to cause a better squeezing sequence of theheart muscle when compared with prior art artificial pacemakers.

Another object and advantage of our invention is to control the electricfield where the Purkinje fibers are located, to take better advantage ofthe Purkinje fibers to cause a better squeezing sequence of the heartmuscle when compared with prior art artificial pacemakers.

Another object and advantage of our invention are a better volumetricfit of the neural electrical stimulation to the optimal heart and/orother tissues target volume, when compared with current art heart,stimulation devices.

Another object and advantage of our invention is to better control theelectric field around the supporting structure Supp from whereelectrical stimulation is injected in the target volume of the brainwhen performing Deep Brain Stimulation, to cause that the electricalstimulation reaches a larger volume of the target volume while betteravoiding stimulating other parts of the brain that are near but outsideand beyond the target volume.

Another object and advantage of our invention is the possibility of timecontrol of stimulation sequences in neural stimulation, which is notachieved with current art devices.

Another object and advantage of our invention is a better control of theshape of the volume of neurons that receive electrical stimulation inbrain stimulation, as in DBS (Deep Brain Stimulation)

Another object and advantage of our invention is a better control of theshape of the volume of neurons that receive electrical stimulation inneural stimulation, as for TENS (Tanscutaneous Electrical NeuralStimulation) pain control in painful persons.

Another object and advantage of our invention is a better control of theshape of the superficial distribution of neurons as for pain control inTENS (Transcutaneous Electrical Neural Stimulation) devices,

Another object and advantage of our invention is a better control andshape of the mostly locally planar electrical stimulation of neurons asused in some cortical brain stimulation. For this, planar but deformablesheets (similar to a bed sheet) are used, to conform to a 2-dimensionalsurface embeded in a 3-dimensional space.

If one or more of the cited objectives is not achieved in a particularcase, any one of the remaining objectives should be considered enoughfor the patent disclosure to stand, as these objectives and advantagesare independent of each other.

Further objects and advantages of my invention will become apparent froma consideration of the drawings, the summary, the description of theinvention and its variations, and the claims.

SUMMARY

It is well known in cardiology that the heart pumping efficiency is adirect consequence of a proper propagation, in time and space, throughall 3-dimensional available electrical paths in the heart cells, of theelectrical pulse that causes the heart contraction, including thecontraction sequence. The fact that the electrical path in the heart isa 3-dimensional quasi-continuous current distribution is not asingrained in the conscientiousness of most workers in the field as Iwish it would. This 3-dimensional current propagation is acknowledged tobe true whether the electrical pulse is the natural one starting at theSAN (sino-atrial node) or an artificial one, starting at the anchoringposition of an artificial heart pacemaker. It is interesting to notehere that evolution does not, and in fact cannot progress alongmodifications on the heart design toward the most efficient possiblepumping, but only to the most efficient pumping from the existingconfiguration—which may well be incompatible with the best solution. Itfollows from this it is not true that the heart that has been evolved bynatural selection is the best solution—and in the case of the heartcontraction it is not the most efficient pumping. Moreover, even ifnature had evolved the best possible contraction sequence, theartificial heart pacemaker does not inject the electric current at thesame location as the natural pacemakers, and consequently the artificialheart pacemaker should correct for this variation. Finally, due to theasymmetry of the heart muscle, it would be expectable that the bestelectrode would include some asymmetry, as required to provide the bestcurrent density around the heart. Consequently, what is needed is aheart pacemaker that could maximize the pumping efficiency, not apacemaker that just makes the heart to pump; just make the heart to pumpis old, we need to do more now, and it is possible to do more, as wedescribe in this patent application. Such a goal of maximizing the heartpumping capabilities has eluded the practitioners because of a lack ofmechanism for precise control of the current injection, in position,direction and relative timing, of the electrical stimulation. Ourinvention is a step in the direction of better control of thisstimulating pulse. Our invention discloses a mechanism to control themagnitude and the direction of the initial current injection in theheart muscle, also time delays between current injected from differentlocations on the surface of the stimulator; in other words, ourinvention affords the possibility of controlling the vector current, andthe relative time at different directions and places, as opposed to onlyits magnitude, as in prior art. Our invention also applies to otherelectrical stimulations as brain (DBS and cortical stimulation), spine,skin, cochlea and others.

DRAWINGS

FIG. 1—A schematic view of a heart.

FIG. 2.—A schematic view of a heart with two implanted electrodes andalso extra field-shaping electrodes of our invention.

FIG. 3—A schematic view of a heart stimulator.

FIG. 4—a schematic view of the stimulator of our invention showingfield-shaping electrodes 140_t 2 of our invention underneath old-styleactive electrodes 140_t 1.

FIG. 5.—A possible implementation of our invention with field-shapingelectrodes at the surface only.

FIG. 6—a schematic representation of our invention.

FIG. 7—a schematic representation of a cordum of our invention.

FIG. 8A—schematic representation of an atrium emptying into theventricle.

FIG. 8B—schematic representation of an atrium emptying into theventricle.

FIG. 8C—schematic representation of an atrium emptying into theventricle.

FIG. 8D—schematic representation of an atrium emptying into theventricle.

FIG. 9A—schematic representation of a ventricle emptying its blood.

FIG. 9B—schematic representation of a ventricle emptying its blood.

FIG. 9C—schematic representation of a ventricle emptying its blood.

FIG. 9D—schematic representation of a ventricle emptying its blood.

FIG. 10—is the gravitational field of the earth including its deviationdue to a large mountain.

FIG. 11A show a calculated field line around three possible electriccharges distributions.

FIG. 11B show a calculated field line around three possible electriccharges distributions.

FIG. 11C show a calculated field line around three possible electriccharges distributions.

FIG. 11D show a calculated field line around three possible electriccharges distributions.

FIG. 11E show a calculated field line around three possible electriccharges distributions.

FIG. 12 shows a stimulator of our invention for the brain (DBS).

FIG. 13 shows another view of a brain version of our stimulator.

FIG. 14 shows another view of a brain version of our stimulator withsome sub-surface field-shaping electrodes of our invention.

FIG. 15A shows a few possible electrode configuration for electricalstimulation.

FIG. 15B shows a few possible electrode configuration for electricalstimulation.

FIG. 16 shows a number of passive electrodes 140_t 2 distributed on awearable shirt-like support Supp_shirt. The fractional surface coveragecould be of the order of 75%, which is the approximate solid anglecoverage offered by the shirt's front+back+sides.

FIG. 17 shows passive electrodes 140_t 2 distributed on a membranesurrounding the pericardio.

FIG. 18 shows a number of passive electrodes 140_t 2 distributed on ahat-like support Supp_hat. The fractional surface coverage could be ofthe order of 60%, which is the approximate solid angle coverage offeredby the hat's front+back+sides+top.

FIG. 19 shows a number of passive electrodes 140_t 2 distributed on awearable belt-like support Supp_belt. The fractional surface coveragecould be of the order of 50%, which is the approximate solid anglecoverage offered by the a wide belt around the abdomen of the patient.

LIST OF REFERENCE NUMERALS

-   BAT1=Battery and controlling electronics box, usually implanted in    the patient's chest.-   MP1=Microprocessor 1. One of the possible units capable of executing    a programmable sequence of instructions, as the venerable 8085, or    the 8086 (which was the brain of the first IBM-PC), 80286, 80386,    80487, pentium, DSP, microcontrollers, etc. Some of these may    include memory, DAC, ADC, and interface devices.-   100=body of picafina of our invention.-   110=electrical energy storage unit (e.g., a battery)+microprocessor    (MP1)+parallel-to-serial converter.-   122=Serial address (may also include return ground, or may use the    same return/ground as power 124).-   123=reset line/control bits.-   124=power conveying means.-   130=ST1=electrical stimulating probe, in the main embodiment is    screwed in the inner part of the heart, brain, or other organs.-   131=anchoring arms to prevent the heart stimulator type (piquita)    from moving back once it is forced into the endocardio/miocardio.-   132=main body of piquita heart pacemaker.-   140-t 1=type1 or active electrodes (standard electrodes, capable of    injecting current in its neighborhood).-   140-t 2=type2 or field-shaping (passive) electrodes (electrically    insulated electrodes, capable of influencing the electric field    lines, but not capable to inject current). Typically type 2,    field-shaping electrodes are covered by a silicon dioxide layer, but    any other insulator is possible, the type of insulator being not    important for our invention.-   210=memory with local address for each electrode 140.-   220=SW=switch to turn electrodes on/off.-   230=comparator to determine if switch 220 should be turned on or    off.-   240=digital comparator/decoder.-   250=enable bit for 260.-   260=comparator/decoder for stimulator addresses.-   307=tricuspid valve, between the right atrium and ventricle. USED-   309=pulmonary valve, exit from the right ventricle. USED-   310atr=atrium. USED-   310ventr=ventricle. USED-   410=hermetically sealed box containing the energy storage unit    (battery), the microprocessor MP1, the serial-to-parallel converter    and all the necessary electronics for the device to operate, as is    used in prior art.-   510=serial-to-parallel converter.-   520=parallel lines for addresses (may also be used for control and    data).-   830=address decoders (AddDec)-   alphabetical labels-   A=digital, binary address lines.-   AVN=Atrial-ventricular node.-   B=power line (voltage or current source).-   bl=blood level. USED-   HB=His Bundle.-   LBB=Left bundle branch.-   LA=Left atrium.-   LV=Left ventricle.-   m=mountain (exaggerated height for display)-   PF=Purkinje fibers.-   RA=right atrium.-   RBB=Right bundle brunch.-   RV=Right ventricle.-   SNA=sino-atrial node.-   SW=also 220 and 810.

DETAILED DESCRIPTION Overview

FIG. 3 shows the main elements of an existing heart pacemaker, which wecall cordum. FIG. 3 shows one of the current art anchoring distalextremities 132tip. Note that different ending anchoring attachments 131are in use, and that the model shown in FIG. 3 uses one of the severalused attachment endings, but the same principles apply to otheranchoring attachments. The main body 132 of the cordum device may have adiameter of 1-2 mm or less (approximate dimensions), and the smalleranchoring side arms 131 may have a diameter of 0.5-1 mm (approximatedimensions, the actual dimension being unimportant for the invention).Anchoring arms 131 should have such size and strength enough to keep thetip of the stimulating cordum structure 132 secured in place once it isinserted into the heart muscle. Anchoring arms 131 should prevent thecordum stimulating device from moving back, out or the muscle, thisbeing one of the reasons for its shape and form, resembling a ship'sanchor, which has the similar function of holding firm to the sand belowthe ship. These dimensions may vary without changing the nature of ourinvention and these values are given as a possible dimension only. Onthe surface of the main body 132 and of the smaller side arms 131 thereare several electrodes, perhaps randomly-shaped, which are representedby either a solid black electrode or by the contour around a whiteelectrode. The solid black odd-shaped patches 140-t 1 representelectrodes which we call active, or type-1 electrodes, and the open,odd-shaped patches 140-t 2 represent electrodes which we formerly calledpassive electrodes, but are now calling field shaping electrodes, ortype-II or type-2 electrodes.

The field shaping electrodes have been disclosed in earlier patentapplications of ours, e.g., patent application Ser. No. 13/470,275 (fromnow on Lee275) currently issued U.S. Pat. No. 8,954,145, and patentapplication Ser. No. 15/019,969 (from now on Lee969), currently allowed,to issue in November 2018, and this invention is a modification of thelocation of the field shaping electrodes, which are called passiveelectrodes in these earlier documents.

FIG. 4 shows another view of the sub-surface electrodes of ourinvention, showing the active electrodes at the surface and thefield-shaping electrodes underneath the active electrodes. FIG. 4 is acut-away displaying a cut parallel and containing the axis of acylindrical supporting structure, with some electrodes 140_t 2 below thesurface and some electrodes 140-t 1 at the surface of the supportingstructure. FIG. 5 is a perspective view but with electrodes only at thesurface of the supporting structure. When 140_t 2 are buried under thesurface of the supporting structure Supp, all the surface electrodes maybe active, which increase the surface available from which to injectcurrent—as there is no need to put field-shaping electrodes on thesurface. At the same time, the available surface for the field-shapingelectrodes is also larger when they (the field-shaping electrodes) areburied—because, if the passive or field-shaping electrodes are buriedunder the surface of the supporting structure Supp, then they can useall the area just under the surface. The sub-surface or buriedconfiguration increases the available surface for both active andfield-shaping type of electrodes, causing an improvement on the deviceover previously described field-shaping electrodes.

FIG. 5 shows a perspective view of the brain-style (a.k.a. Picafina),with some wires down the length of the device, but not all wires toprevent cluttering the drawing. Only the wires that make the connectionto the electrodes at the top layer 320 are shown. Other electrodes, onthe layers below (330, 340, etc.), are also connected to dedicatedwires, similar to the ones shown in this figure. In the main embodimentthe wires are of the printed circuit type, but lose wires are alsopossible, though a smaller number of them would be possible. At the topof the brain-type picafina shown in FIG. 5 there is an electricalconnector, which is capable of matching another connector with wiresleading to the battery/controlling electronics implanted at anotherlocation, as in prior art.

Whether the device in question is a cordum (for the electricalstimulation of the heart), popularly known as an [electric] pacemaker,or a picafina, adapted to cause an electrical stimulation on certainparts of the brain, as the sub-thalamic nucleus, the globus pallidusinterna, etc. they all have a common structure: a body, a battery orsome other source of electrical energy, an electronic control unit,which usually, but not necessarily is a digital device, a supportingstructure adapted to keep electrodes at a fixed position with respect tothe animal, and wires connecting these elements. We call the combinationof these parts as an electric stimulating assist system.

The field shaping electrodes of our invention may be located at thesurface of the supporting structure Supp or under the surface of thesupporting structure Supp. The possibility of locating the passive (orfield-shaping electrodes) below the surface of the supporting structureSupp causes a most important improvement on the electrical stimulatingdevice, which is that the whole surface of the supporting structure Suppcan then be dedicated to the active electrodes, allowing more optionsfor the electrical stimulation. The reader should note here that movingthe passive electrodes to below the surface of the supporting structureSupp also increases the available positions for the passive electrodes,because the passive electrodes need not be sharing precious real estatewith the active electrodes. Of course that the passive electrodes mayalso be located at the surface of the supporting structure Supp.

Once any passive electrode is connected to the battery and controllingelectronics by electrically conducting wires, the electric potential ofthe electrodes can be varied according to the instructions saved in thememory of the controlling electronics, which in turn determine the value(and signal) of the electric charge stored (forced) in the electrodes;call this charge q. Elementary physics then shows that this electriccharge q can contribute to the value of the electric field in the spacesurrounding the electrode supporting structure Supp. Moreover, theelectric field, and therefore the force on electric charges propagatingin the volume in question is determined by the formula:

E-vector=[k*(q1)/d**2]*r-hat

F-vector=q2*E-vector

where E-vector, F-vector, etc. (also E-field, F-field, which is the samebecause the field in question is a vector field) indicate that thequantity in question is a vector, and r-hat indicates a unit vector withthat name, which, in this case is along the line connecting the twocharges q1 (which is originating the electric field, and q2, which isunder the influence of q1, or under the influence of the electric fieldcreated by q1, and the force F-vector is the force that acts on q2. Thecommon notation is to make E-field, F-field, etc. in boldface, which maynot be available at the USPTO press, so we avoid the bold face useconvention. This force F-vector has to be determined beforehand (thatis, calculated), to be such as to cause such a force on the propagatingelectric charges, usually in the forms of ions, that these electriccharges stay on a desired volume (in the DBS brain case) and also, inthe case of the heart, propagate at such a speed along the heart musclethat the muscle contraction causes as complete a pumping asfeasible—given the poor design of the heart by the intelligent designer.In general the passive electrodes should be set at such an electricpotential that the electric charges propagate within a desired velocity(speed and direction) that the electric charges stay within a desiredvolume.

Active, or type-1 electrodes 140-t 1 have a metallic surface (or otherelectrically conducting surface) which is capable of conductingelectricity. Other than their smaller sizes and odd-shapes, theycorrespond to the prior-art electrodes for electrical stimulation of theheart, brain, and other body parts, from which they only differ in shapeand size but otherwise being electrically and functionallysimilar—though their size and configuration add to their functionality,as explained below. Field-shaping, or passive, or type-2 electrodes140-t 2 (all equivalent names for the same element) also have a metallicsurface, but their metallic surface is covered by an insulating layer,which may be made of silicon oxide but other materials are alsopossible. Field-shaping, or type-2 electrodes are unable to injectcurrent into the surrounding tissues, but when set at fixed electricpotentials (voltages). The field-shaping electrodes change the shape ofthe electric field in the neighborhood of the cordum, therefore changingthe paths of the injected currents. Field-shaping (type-2) electrodesare incorporated in the cordum for the purpose of shaping the electricfield configuration (to change the spatial configuration of thesurrounding electric field which in turn changes the path of theelectrical stimulation).

We want to anticipate here to the reader that the passive electrodes maybe anywhere in the patient: the passive electrodes may be near theactive electrodes, they may be near or far from the target volume (thevolume that is electrically stimulated), the passive electrodes may bewrapped around, covering partly of or totally the target volume, asschematically shown in FIG. 17, where one sees a surface covering aheart, see also references (1), (2) and (3), they may be on the wiresthat connect the battery to the electrodes, they may be on anysupporting structure elsewhere in the patient, which may be designedespecially for the purpose of holding the passive electrodes in fixedposition with respect to the patient, and among these supportingstructures elsewhere in the patient, some may be implanted under theskin of the patient, others may be attached to the skin of the patient,but on the outside of the skin, others may be worn outside the patient,as passive electrodes attached to a shirt (see FIG. 16), or to a hat(see FIG. 18), or to a belt (see FIG. 19), etc. An example of asupporting structure Supp wrapped around a target volume is seen at FIG.17. In this FIG. 17 one can see a schematic representation of passiveelectrodes 140_t 2 distributed on a membrane surrounding the pericardiaSuch a membrane was developed, fabricated and actually used on arabbit's heart ex-vivo (ref. 1, 2, 3). In this case the membrane aroundthe rabbit's pericardium was populated with data collecting sensors, aspressure sensors, electrical reading electrodes, pH sensors, etc., andthey took the heart out of the unfortunate rabbit, then kept it beatingwith a heart pacemaker and a heart-lung machine while making thephysical measurements. Our device would have passive electrodes on themembrane instead, so it is a simple modification of an existingtechnology. Another difference between our work and the work of LizhiXuet al. referenced above is that we will murder no rabbit.

FIG. 18 displays a similar device, this time supported by a hat, asupporting structure Supp called Supp_hat. Supp_hat has passiveelectrodes 140_t 2 around the hat, which create an electric fieldE-vector in the volume of the head of the patient, useful for DBS,cortical stimulation, etc. In the case of the FIG. 18 the hat is of thetype of a baseball hat, but this particular style is not the only one,any hat-like structure being equivalent, as the type of hat does notmatter. Instead of a hat the same objective can be achieved with abandana, or similar fashion devices, as long as it is a supportingstructure in fixed position with respect to the head (and brain) of thewearer.

FIG. 19 displays another similar device, this time supported by a belt(Supp_belt), a wide belt of the type used by persons lifting heavy loadsfor either work or for sports. In this figure one can see a number ofpassive electrodes 140_t 2 that are suitable to create an electric fieldE-vector in the belly of the wearer, perhaps to help some stomachelectric stimulation, as for appetite control or some other objective.In this case shown at FIG. 19 the belt Supp_belt is wide, as is the beltto protect people from possible damage caused by lifting heavy objects,but the belt may also be narrow, say, 3-6 cm (1-2 inches), as are thenormal belts used to keep the pants in place, only that a narrower beltwould have less effect than a wider belt as shown. But the width of thebelt does not change the nature of having a supporting structure at theabdomen of the patient that is receiving electrical stimulation.

In this patent application we suggest passive electrodes on the wiresthat go from the batteries to the electrodes themselves, and also onother supporting structures especially designed as a support for thepassive electrodes, as described elsewhere in this patent application,as shirts (FIG. 16), hats (FIG. 18), belts (FIG. 19), (outside thepatient) and on other supporting structures wrapped around some organ(FIG. 17), etc. In fact there are an infinite number of locations forthe passive electrodes, which are covered by variations of thesupporting structures disclosed on this patent application. Thesesupporting structures may wrap around the heart, the chest or parts ofthe heart or part of the chest of the animal, or the supportingstructures may wrap around the brain, the head or parts of the brain orparts of the head of the animal, or the supporting structure may wraparound the stomach, the abdomen or parts of the stomach or parts of theabdomen of the animal or of the patient.

To physically achieve the above description, the controlling mechanism,in this case a microcontroller MC1 residing in the battery/control unit110 (FIG. 6), is loaded with a program (or software), which is capableof executing automatic repetitive tasks following a programmed sequencethe details of which are adjusted by a medical professional or by thepatient himself, which determines a particular combination of active andfield-shaping electrodes to use, also able to determine which electrodesof each type to use, also able to send this information by wires to thestimulating unit 132. The correct sequence can be determined, forexample, by the examination of an EKG (Electro Cardiogram) while varyingthe active electrodes of each type, their electric potential (voltages)and relative time sequence. Microprocessor MP1, located in box 110,select which wires 124 to be connected to electric power and theelectric potential (voltage) level as well, which may be different ateach wire 124. Each were 124 connects to one of the electrodes 140-t 1or 140-t 2. Each electrode type can be turned on or off (connected ordisconnected from the electrical power) under the control ofmicroprocessor MP1.

The invention also discloses an important marker to determine theangular position of the cordum (or picafina for the brain, or otherequivalent device for other organs, neurons, etc.) with respect to theheart (or brian, organ, etc.) in which it is implanted. FIGS. 3 and 6show one such possible marker: a type-1 active electrode 140-tm withsuch an X-ray opacity (absorption) to be visible during the fluoroscopicimages taken during electrode implantation as normally done. Othermarkers are possible for the same purpose, as the same shapes on type-2field-shaping electrodes, as side arms 131 of different lengths and/ordiameters, or any other asymmetric feature that is visible in some sortof imaging technique, as MRI, X-ray, ultrasound, etc. It is part of ourinvention that each electrode position and size and orientation is knownto the cardiologist (and the computer which he will use to program thedevice), each electrode being know by a designator, as a number, as 1,2, 3, . . . etc., or any other alphabetical or numerical pattern or anyother naming system as desired. Marker 140-tm allows for the computerprogram to know the angular position of each electrode, which is neededto determine which individual electrode to connect to which electricpotential (voltage), according to their actual position within the heartmuscle, as the cordum happened to have been anchored in it.

Inside the main body 132 and the side arms 131 of the cordum supportingstructure, there are wires 124 extending from the controllingelectronics, microprocessor and battery to each electrode 140 (of eithertype, t1 or t2). Wires 124 may be either standard wires or may also beprinted wires, as in printed circuit boards. The technology of printedcircuits is a well advanced technology with many methods to print thewires, and the wire manufacturing is not part of this invention, as anyof the existing technologies are acceptable to implement the invention.

The main embodiment uses 10 wires from the battery pack/control unit 110to the cordum supporting unit 132, which are connected to the 10available electrodes 140 by the 10 wires 124—one wire for each electrode140. This particular choice of 10 wires and 10 electrodes should not betaken as a limitation on the invention, because more wires andelectrodes, or less wires and electrodes are possible still within thescope of the invention, as obvious to people familiar with the art ofelectronics. It is also possible to connect the ground (or return) wireto any number of electrodes (or pads), both type-1 and type-2

The random placement, shape and size of the electrodes is a distinctfeature of our invention, as it contributes for the creation of aspatial asymmetry of the electrodes, which in turn causes an asymmetryin the spatial distribution of the injected current, either itsmagnitude or its direction. Careful selection of which electrodes toturn on, and at which electric potentials (voltages) can create the mostdesirable electric field shape on the volume of the heart. A carefulselection of which electrodes is able to produce a better resultingstimulation which is suited to the asymmetric heart muscle 3-dimensionalshape and causes a more complete squeezing sequence and better ejectionfraction (the fraction of blood sent out of the heart). It is to benoted that if any symmetry is required, our invention is backwardscompatible, being able to reproduce old art stimulating surfaces as aparticular case of an arbitrary shaped surface. Note that if a symmetryof current magnitude and direction is desired, it can still be achievedwithin a reasonable accuracy, by the appropriate selection of a numberof electrodes which, as a set, defines the desired symmetry. Naturallythe degree of symmetry possible to be achieved depends on the number ofelectrodes available: more asymmetry with more electrodes (that is, morecomplex electric fields with more electrodes)

FIG. 7 shows a variation of the heart-type stimulator cordum withelectrodes only at the surface of the side or anchoring arms 131. Forsimplicity this figure does not differentiate between the two types ofelectrodes 140-t 1 and 140-t 2, but it is understood that the generaldenomination 140 intends for both types of electrodes, either randomlyor orderly distributed on the surface of 131.

The improvement of the invention is to bury at least some, potentiallyall the field shaping electrodes under the surface of the supportingstructure 131 and 132. With this geometry the full surface of thesupporting structure 132 and 131 is available for the active, orelectric current injecting electrodes, which in turn increases thepossibilities for controlling the 3-dimensional current through theheart—or through the brain in DBS, or through another organ, or anothernerve, etc. The buried electrode, which we also call subterraneanelectrode, functions in the same way as the passive electrodes disclosedin the previous inventions (Lee275 and Lee275 and Lee969) but addfunctionality to them because more surface becomes available for theactive electrodes and also, more important, the field shaping electrodeshave more control on the electric field because they form a morecontinuous surface enclosing the volume inside, as predicted by the Laraconjecture, which, in the weakest form, states that it is possible tocreate an electric field that is almost the same as any desired electricfield in any volume V that is completely enclosed by a surface S_(cl)provided that one has strong control on the electric charges on most ofthe surface of S_(cl). With an eye on the Lara conjecture, we proposeanother improvement on the supporting structure for the buried orsubterranean electrodes, the improvement consisting on a supportingstructure that allows buried electrodes at a surface that almostcompletely encloses the target volume. For example, for the heartpacemaker the enclosing supporting structure could be a sac sutured onthe outer surface of the heart, just outside and beyond the pericardium,as shown schematically at FIG. 17. Such a sac has been used ex-vivo onthe heart of a poor rabbit (without his consent, the inventor believes),as described at references 1, 2 and 3. Such a surface would require afew holes for the arteries and veins in and out of the heart, but itcould enclose 90% of the heart (or, in other words, the holes for thearteries and veins would be less than 10% of the total surface. Orperhaps less than 90%, as only 70% or even 50% of the imaginary surfaceenclosing the heart just beyond the pericardium Or such a surface aroundthe heart could be a shirt with the buried or subterranean electrodes onit that could be worn by the patient, as shown in FIG. 16. Such a shirtwould cover perhaps 60% to 70% of the surface around the heart, which isa small fraction of an enclosing surface, but it would have two majoradvantages over the surface right on the outer surface of the heart that(1) it would require no surgeries and (2) the batteries could be changedeasily, which is not the case for the implanted surface on thepericardium. Advantage number 1 above would be good for the patient butbad for the surgeon, so it would not satisfy all parties, but thisshould not be an argument against the device we disclose here.

Alternatively, this external surface holding passive electrodes at itssurface or below its surface could be smaller than a shirt, as a belt,perhaps a wide belt similar to the belts used to hold the belly of aperson who is lifting weights, as for working, as shown at FIG. 19 butit could be narrower too, even of the width of a standard pants belt, as2 to 5 cm (1 to 2 inches). Such a belt could be useful for electricalstimulation of the stomach, as for appetite control.

In general terms, any of the variations for the heart pacemaker thatwraps around the heart or parts of the heart, or the chest or parts ofthe chest of the animal, or the head or parts of the head of the animal.

Another type of electrical stimulation that is becoming more common isfor the stomach, etc., for appetite control and other uses. Such anelectrical stimulator could wrap around the stomach or parts of thestomach, or the belly or parts of the belly of the animal.

For the brain, such an enclosing surface could be a malleable surfaceeither just below the skin at the head or under the cranium. The formercase (below the skin) would be easier to implant than the latter case(under the cranium). Such a surface would not completely enclose thebrain either, but it would be capable of having a strong effect on theelectric charges propagating in the brain. On one embodiment thealmost-enclosing surface would have a hole at the bottom for the neuronsto pass into the spine, with other holes for the neurons that bring inthe visual input, the aural input, etc. On another embodiment, giventhat the hole at the bottom of the brain would have the largestdiameter, when compared with the hole for the visual input, aural input,etc., the neurons leading to the spinal cord could be severed, obviatingthe need for this larger hole. Given that the brain is so rarely used bymost people, this severing of the connections to the spinal cord wouldcause no discernible effect on most people.

Or, similarly to the shirt with underground electrodes for heartpacemaking applications, an external surface to support passiveelectrodes for brain stimulation (as in DBS) could take the shape of ahat worn by the patient taking any of the common types of hats, from acawboy hat to a baseball cap, or other types, as shown at FIG. 18. Sucha hat could also have an extension at the back of the head, of the typeused to block the sunlight from the back of the neck, used by manyworking people, and/or an extension around the neck, of the type used asscarf in cold places. Both the extension at the back of the head and theextension of the type used as scarf would increase the surface area fromwhere passive electrodes could create an electric field inside the head,which would increase the strength of the device. As the reader can see,many variations are possible, with the supporting structure bothimplanted near or just around the target volume, and external to thebody as well.

As the reader can see, there are many variations of the brain pacemaker(as for DBS) that wraps around the brain or parts of the brain, the heador parts of the head of the animal.

OPERATION OF INVENTION Background Information on Operation of theInvention

To understand the operation of our invention, the reader must keep inmind what causes the heart to contract, and therefore to pump the blood,and the sequential nature of this contraction as well. FIG. 1 displays ahuman heart with the main parts indicated in it. Left and right aredesignations from the point of view of the person in which the heart is,which is the opposite of the viewer, facing the person. The right andleft sections are responsible for two independent closed cycle bloodflow: the right side of the heart pumps blood to the lungs then back isthe pulmonary circulation, while the left side of the heart pumps bloodto the whole body.

The heart muscle contraction occurs as a consequence of and followingthe propagating electric pulse that moves in 3-D (three dimensions)through the heart muscle from an initiating point (the sino-atrialnode), which is located at the top of the right atrium—the 3-D electricpulse propagation through the heart muscle is important for theoperation of our invention, as it will be seen in the sequel. Thispropagating electric pulse is known by the medical people as adepolarization wave, and the medical people associate a depolarizationevent to a muscle contraction event. This sequential contraction,characteristic of all peristaltic pumps, is similar to the process ofsqueezing toothpaste out of the tube: it is a progressive squeezingsequence which progress from the back to the exit port, as opposed to asimultaneous contraction from all sides. Granted that there are peoplethat extract the toothpaste squeezing the tube from the middle, but itis universally acknowledged to be inefficient to do so, even by the verypeople that do it; they make a huge mess and drive other family memberscrazy trying to fix it all the time. The heart squeezes as a properlyused toothpaste tube, not as a collapsing air balloon that collapsesupon itself from all directions at the same time. Yet, the heart is notas good as it should be at squeezing from back to exit, and outinvention improves the heart, directing it to go into a properlysequential squeezing.

One of the reasons for the lack of appreciation of this sequentialcontraction is that it is not perfect, as if it occurred within awell-engineered pump. Moreover, the heart is more or less hanging insidethe upper torso, suspended by the blood vessels and somewhat resting onthe diaphragm, as opposed to a proper peristaltic pump, fixed inrelation to the machine in which it works. As a consequence of this, theheart twists and moves on all directions as it pumps, a dance maskingits sequential motion. This dance of the heart, this twisting on alldirections, should have been already noted as a sign that the electricpulse propagation along the heart muscles is not uniform, and thattherefore neither is the contraction propagation symmetric around theheart, downwards at the atrium and upwards at the ventricles. Lastly,each half squeezes in ½ second, too short a time for a human being toperceive in detail other than from a slow motion video.

This sequential contraction is valid for all four heart chambers: theright atrium, which has its entrance at the top and exit at the bottom,contains the initiating electrical cells at its top (the sino-atrialnode), from which the electrical pulse propagates in its muscle wallsfrom top to bottom, which is, accordingly, the sequential squeezing, asper FIGS. 8A, 8B, 8C, and 8D (the figure exaggerates and distorts thesituation for display purposes and because the inventor is unskilled indrawing too). The ventricle, on the other hand, has both entrance andexit ports at its top, which poses a difficult problem to solve, needingas it does, to contract from bottom to top, to force the blood to exitat the top, while the electric pulse is coming from the top! This wassolved by the intelligent designer with a mechanism to arrest theelectric pulse at the bottom of the atrium (else the ventricle wouldcontract from top to bottom, where there is no exit point for theblood!), and another specialized set of cells, the atrium-ventricularnode, which, upon receiving the weak electric signal that is coming downfrom the sino-atrial node, re-start another electric pulse, but with afew milliseconds delay, which is in turn delivered for propagationthrough a set of specialized fast propagating cells lining the wallbetween the two ventricles: the His short bundle, followed by the rightand left bundles, and finally the Purkinje fibers that spread theelectrical pulse throughout the bottom and sides of both ventricles.This second electric pulse, delayed from the initial pulse from thesino-atrial node, is then injected at the bottom of the ventricles, fromwhere it propagates upwards, causing an upwards sequential contraction(in the opposite direction as the initial atrium contraction!), asrequired by an exit point at its top. This process of upwardscontraction of the ventricle, the lower chamber, is displayed in figureFIGS. 9A, 9B, 9C and 9D. It works, though any respectable engineer wouldhave made a different design, with a ventricular exit at the bottom, notat the top, but at least one can take solace in that this is not theworse design error of the human body—one just has to look at the brain.

The left heart pumping in essentially the same, varying only in minordetails, there is no need to repeat.

This said, the reader should keep in mind two important points herewhich is the detail on which the whole invention hinges, and which weurge the reader to pay attention and ponder on. First, that not only isthe heart contraction caused by an electric pulse but also that thiselectrical pulse, because it relies on the propagation of heavy positiveions in a viscous medium, it propagates relatively slowly through itsmuscles and special fibers. The propagation of this electrical pulse isvery slow as far as electric events happens, the whole process takingjust below one second to complete (at a normal heart beating rate of 70beats per minute). This means that the times involved are of the orderof 10s and even 100s milliseconds. This slow propagation time isimportant for our invention to work, as it will become evident in thesequel. The much faster propagation of electric charges in wires andtransistors (1 million times faster), allows that a human-engineeredcircuit can take over the natural process and improve on it—a veryinteresting project indeed!

In this main embodiment, the variation and improvement over our previouscited patents Lee275 and Lee969 is that at least one (and perhaps asmany as all) the field shaping electrodes (called passive electrodes inthese two older patents applications) is placed under the surface of thesupporting structure, as 131 and 132 for the cordum. This has two majoreffects. The first consequence is that once the field shaping electrodesare located under the surface of the support, it follows that there is alarger surface area available for them, which, in turn, causes thatthese subsurface electrodes can fulfill better the Dirichlet's condition(see below) for a closed surface completely enclosing the desired volumewhere one intends to adjust the electric field. We remind the readerthat the electric field created by these subsurface electrodes isconfigured to apply a force on the propagating electric charges in thespace surrounding the electrodes or surrounding the body of the electricstimulating assist system, guiding the propagating electric charges on atarget path and/or to keep the propagating electric charges inside atarget volume. The target volume may be a part of the brain, as thesub-thalamic nucleus (for DBS), or a part of the heart, as the walls ofthe heart muscle. The problem of the heart is more complex than theproblem of the brain, because the heart requires a charge propagationthat causes an efficient peristaltic pumping of the heart, with aforward squeezing of the heart.

The second consequence is that once the field shaping electrodes arelocated under the surface of the support, there exists a largeravailable surface area to be occupied by the active electrodes, orelectric current injecting electrodes, which in turn increases theoptions for the electric current injection in the tissue.

Another improvement on the system we are describing here is thepossibility of an addressing system with associated memory, which isalso capable of receiving data conveyed by electromagnetic waves, asradio waves, FM, and higher and lower frequencies, which carry theaddresses and other information necessary for the selection of aplurality of one or more electrode of each type (active andfield-shaping electrodes) to be active, and also the electric potentialvalue (voltage level in American parlance). Such system and manyvariations of them are disclosed in many other of our patents,particularly U.S. Pat. Nos. 8,335,551, 8,509,872, 8,538,516, 8,565,868,8,738,135, 9,037,242 but also other patents too.

The shape and size differences for the electrodes is not necessary forthe main embodiment, which would also work with stimulating activeelectrodes (and non-conductive field shaping electrodes) of the sameshape and/or size. The invention is the same for simpler electrodearrays which may be simpler and less expensive to produce, such a choicebeing a matter of production/cost compromise, still under the scope ofthe main embodiment. For example, it is possible to control the vectorinjected electric current (magnitude and direction) with circularelectrodes (of either type, conductive or current injecting andinsulated or field shaping electrodes) that are of different sizes andrandomly distributed on the surface of the cordum. It is also possibleto control the vector injected electric current with circular electrodes(of either type), that are of the same size and randomly distributed onthe surface of the cordum, in this more restrictive case, same shape andsize but randomly distributed on the supporting surface. Or it is alsopossible to control the injected electric current vector with circularelectrodes that are of the same shape and size and orderly distributedon the surface of the cordum, this being the most symmetric electrodearrangement of all. The difference between these options is simply thedegree of possible variations and fine control on the vector current,and the choice between each option is based on a cost/benefit analysis,all being still within the scope of our invention.

A moment of thought will show the reader that the good operation of theheart depends on the propagation of the electric current. This latterdepends on the electrical characteristics of the diverse muscles (cells)which comprise the heart, including rapidly electric propagating cells(His fibers, etc), endocardio and miocardio cells, the electriccharacteristics of which suffer individual variations from person toperson, due to their genetic make-up, to which other variationsaccumulate during the person's lifetime, due to his exercise and eatinghabits, etc, to which unlucky events as small localized infarctions addscar tissues to do possible broken hearts in the youth of the person,each described by a potentially lower conductivity and loss ofcontraction capability, all adding to a conceptually simple problem, yetof complex analytical solution. This, in turn, is the problem which ourinvention address: how to better adjust the 3-D electric currentpropagation through the heart in order to cause the best heart squeezingsequence possible for a particular individual, given his possibilitiesas determined by the physical conditions of his heart at the given timewhen the device is installed in the patient.

Another way to say the same thing is to notice that unlike a standardelectrical network, on which the paths are discrete and fixed, theelectrical path for the current that produces the muscle contraction iscontinuous over the whole 3-D structure of the heart, and some leak outof it too, being measured as EKG signals on the chest. Because theformer, a standard electrical network is composed of discrete,enumerable paths, the information is given as the denumerable branchesand nodes, while in the latter case (the heart) the information is acontinuous current vector field.

Besides selecting which electrodes are turned on or off (connected ordisconnected from the electrical power), the controlling microprocessorMP1 can also select one of a plurality of electric potentials (voltages)to be connected to the electrodes. Varying the electric potential at thefield shaping electrodes, the device can adjust the electric field inits neighborhood, and therefore it can adjust the path of the electriccurrent that is injected elsewhere by the active electrodes. Moreover,the improvement we disclose in this document discloses buried, orsubsurface field shaping electrodes. This offers an advantage over priorart because out invention can better direct the electric current to theparticular desirable target volume and avoid entering into undesirablevolumes. Also, varying the electric potential (voltage) at the activeelectrodes, the device can adjust the magnitude of the current that isinjected into the heart.

The Electric Field Lines.

The solution to this problem is found in the theoretical analysis ofelectric current propagation within an electric field. As a side remark,this is similar to the motion of an object by gravity within thegravitational field of the planet, which is vertical towards the centerof the planet assuming a perfectly spherically symmetrical Earth. Allobjects, unless prevented from falling by some means, do fall down inthe direction of the center of the Earth, on a straight vertical line.The earth gravitational field is set of lines radially pointing to itscenter, as most of the fields in FIG. 10. FIG. 10 also display twogravitational field lines next to an exaggerated large mountain, which,due to its large mass tilts the gravitational field lines sidewaystowards the mountain. An actual large mountain does, surprisinglyenough, minutely deflects the gravitational field from its “normal”direction towards the center of the earth, and in amounts that aredetectable with modern equipment (see an exaggerated off-radialdisplacement near the mountain at FIG. 10). This, of course, happensbecause the mountain attracts sideways. Another example is an automobilewhile driven by a person at the driver's seat. The driver is capable ofpressing on the gas pedal, which detonates a sequence of events thatculminate on a faster speed of the car, and turning the steering wheelthe driver detonates a different sequence of events that culminate onthe change of direction that the car moves. Both of these, the speed andthe direction are controlled by the electric field lines acting on avolume where electric ions (Ca, K, etc., in a heart) can move in severaldirections and at different speeds as they are acted by the electricfield lines, as shown below.

Given that

F(vector)=q×E(vector),

It follows that the force, and consequently the acceleration and thenthe motion of an electrically charged particle starting from rest aredetermined by the electric field lines. The electric field can take morecomplex configurations than the gravitational field, because there aretwo types of electric charges (usually called positive and negative),while the gravitational field is due to only one type of gravitationalcharge (called mass, they all attract each other). FIGS. 11 (A, B, C, Dand E) displays five types of simple electric field configurations:Figures FIG. 11A and FIG. 11B display two cases of field lines that aresimpler to calculate, of two electric charges, in fact the configurationnormally seen in introductory physics books, books used in middle schoolin most of the world, and used at university courses in USA. The fieldlines are the lines along which forces act on electric charge moving inthe volume. In other words, the field lines control the flow path of theinjected current. From this it follows that to shape the electric fieldlines is the same as to lay down the “roads” where the current willtravel whenever charges are set free in the region. This notion ofshaping the field lines to determine the current path is seldom usedonly because in most electric circuits the current (charge) is forced tofollow the wires, the coils, the transistors, etc., with no place for anexternally imposed electric field to have any effect. FIG. 11C shows amore complicated case with three charges. The reader is invited toobserve the large change of the configuration of the field lines causedby the addition of this third charge, in particular the disappearance ofthe symmetry that is obvious in figures FIGS. 11A and B. FIGS. 11D and Edisplay the effect of varying the value of the third charge. Again thereader is invited to ponder on the consequences of varying the values ofthe charges. Notice that both FIG. 11D and FIG. 11E are asymmetric, yetthe shape of the field lines is vastly different between them!

The electric field lines are distinctively unequal, very differentshapes. Not displayed is also their strengths, which is also distinct,left out to simplify the figure. FIG. 11 illustrates the point of ourinvention: a method and a means to conform the electric field lines tothe desired 3-dimensional shape required for a most desirable heartsqueezing sequence. In fact, using the cordum of our invention, it ispossible to even create a 3-dimensional electric field which causes abetter heart squeezing sequence than the sequence that happens in anormal, healthy heart, because a normal, typical, healthy heart does notactually follow the best possible sequence due to its design having beenunintelligent.

Setting each small electrode at the sub-surface of the cordum at adifferent electric potential (which causes a different electric charge Qon each electrode), a different electric field is set in itsneighborhood. The cardiologist, or any other medical personnel, using acomputer program to display the electric field created by any particularcombination of voltages, will adjust the voltages at differentelectrodes and see, on the computer screen, the 3-dimensionalconformation of the electric field created by them. This is one problemof the class known as “inverse problems”, a technical name given inmathematics for problems in which a particular cause is sought (aparticular distribution of electric potentials (voltages) on the surfaceof the cordum) which will cause a particular 3-dimensional electricfield configuration over the heart muscles. Mathematicians have goosebumps when they are presented with an inverse problem, because they knowthat most inverse problems have no solution (no closed form solution, tobe precise), which is the case of this one. Its solution is found bytrial and error, adjusting a new electric potential at the field shapingelectrodes and noticing if the new electric field got closer to thedesired one or farther away from it. From this, readjust the electricpotentials and observe the result again, and again, etc. Though this mayseem a tedious solution, it is easier than working from scratch, becausethe hearts are approximately the same, and the pacemakers are implantedin approximately the same places, which means that the general type ofsolution needs to be found once and for all—then only smalleradjustments are necessary. In any case, if so desired the cardiologistcan set all the active surface to be at the same electric potential(voltage), in which case the “improved” electric stimulator (pacemaker)would be working in the same way as prior art pacemakers. In practice,the inventors believe that even without individual adjustments, and onlyusing the best average selection of surface distribution of electricpotentials (voltages), there would be some improvement over prior art.

Current art of heart pacemakers uses two and even three individualelectrodes, for example, one electrode near the sino-atrial node (at thetop of the right atrium), and one near the bottom of each ventricle(right and left). Using these multielectrode stimulators much enhancethe performance of our invention, because they increase the number ofavailable points over which there is control for adjusting the electricpotential (voltage V, as the Americans say) (or charge Q, which is thesame thing), and also at much larger distances between them. Morecontrol is possible with the modern two- and three-stimulators than withthe one single electrode at the top of the atrium.

Besides the directional electric current flow, which is started again atevery heart beat at the sinoatrial node, the local reactance plays arole, as it determines a 3-dimensional continuous network whichdetermines the time delay and magnitude of the local electric pulse,which in turn determines the local timing and strength of the localsqueezing. Incorrect time delays of the electric pulse are costly forthe pumping efficiency, because since they are the very cause of themuscle contraction, that is, of the pumping, and therefore time delayson the ion propagation through the heart muscle are reflected in timedelays in the contraction sequence. Localized higher or lowerresistivity are costly too, because they change the electric currentdensity, which in turn decrease or increase the strength of the musclecontraction, that is, of the pumping pressure, either way decreasing thetotal pumping volume. Our invention, as it adjusts the magnitude and thedirection of the electric field throughout the heart muscle, correctsfor these errors that accumulate throughout the life of the person, asthe heart ages and changes. For example, in locations which, due to thechanges that occurred throughout the life or due to genetics, theresistivity is larger (which decreases the electric current and itsspeed), they can be countered with a locally larger magnitude electricfield.

Taken together, controlling the direction and the magnitude of thecurrent, our invention is capable of controlling the position and themagnitude of the squeezing sequence.

Introduction to the Mathematical Treatment of the Problem of the BestElectric Current Distribution Over the Heart Muscle.

It is a well known result in electromagnetic theory that any arbitraryvector field inside an imaginary closed surface obeying the Maxwell'slaws the govern the electric and magnetic fields can be createdadjusting the electric charge distribution at the surface that enclosesthe closed volume (see Reitz, Milford and Christy (1980), Jackson,(1975) or most any other introductory text in electromagnetic theory).This physical statement is related to the Dirichlet's principleDIRICHLET (n/d). But the reader is reminded that the Dirichlet'sprinciple applies to electromagnetic waves described by the known 2^(nd)order differential equation, which is not the case here, because herethe electric field is static, not dynamic. In our case the stimulatingdevice does NOT have total control, because it would be impossible toset electric potentials (voltages) at unconstrained values (the electricenergy source (or electric energy storage unit)/battery is ratherlimited on its maximum output), nor do we have access and control oversome surface that completely encloses the heart (or the brain, etc.),which means that not all desired vector fields are possible. Yet,adjusting the available electric potentials (voltages) over theavailable surface on the device in the vicinity of the desired volume itis possible to have a certain degree of control of the current vectorfield over the heart volume, and consequently to have more control onthe path and speed of the injected electric electric charges and betterresults for the patient. This is even more correct when the cordumstimulator is, as is becoming more common nowadays, a three independentstimulators, one at the top right atrium, one at the bottom of eachventricle. Our invention does not create a total control on the fieldlines, our invention cannot create all arbitrary field shapes, but ourinvention can shape the field to a better conformation than old artwhich offered no control of it. In fact, to the best of the knowledge ofthe inventors, nobody before have ever tried to control the electricfield shape on the heart muscle to control the current through it. It isto be noted that the invention disclosed in this document allows for alarger Dirichlet surface surrounding the volume of interest then thedevices described in the two previous invention disclosure of ours:Lee275 and Lee969.

Dirichlet's problem is discussed in books dealing with electromagnetismbecause it is much related to the problems of interest in the field, yetit was initially developed out of its mathematical interest, and it isalso discussed in many books in differential equations.

This mathematical theory indicates that our invention works better witheither a larger area supporting electrodes (which approaches a totallycontaining surface) and also with just a few small electrodes spreadapart, as in the two- and three-electrodes of current heart pacemaking,anchored as they are, at the top of the right atrium and bottom of eachventricle.

Therefore our invention is the use of a controlled charge distribution(or voltage, which is the same, because one determines the other) overas large an area as feasible, with the objective of adjusting theelectric field lines over the heart muscle so that the injected currentcauses a downwards moving current from the top of the atrium to theboundary between the atrium and the ventricle, then either anothercurrent through the His bundle, right and left bundles and Purkinjefibers, or else simply another starting electric current originating onanother implant at the bottom of the ventricle, possible if thecardiologist decides to use a two-electrodes pacemaking system.Moreover, the surface electrodes can be of either type 1 (active) ortype 2 (field shaping). The first type of electrode can be eitherstarting or finishing points for electric current paths, while thesecond type of electrodes is able to bend the field lines but not ableto inject charges, because it is electrically insulated (though it canact via capacitive effect, as well known to the persons versed in thefield of electrical engineering). Finally, given that the times involvedare very long for electronics, a typical heart period being almost afull second and its P, Q, R, S and T waves lasting from a few to 100smilliseconds, while microsecond is easy in electronics, it is perfectlyfeasible to activate electrodes or either type (active or field-shapingtypes) then turn them off sometime before the slowly moving electriccurrent arrives at the electrode, therefore forestalling theestablishing of a terminal point for a current. This can be dynamicallyadjusted to keep the current moving along a desired path, while neverabsorbing it. This selective adjusting of the ending points of anelectric field line is effective in creating strong field lines with theuse of electric charges near the initiation point of the current, whichin turn is made to disappear as the current nears intermediatepositioned electric charges, which may be substituted by other chargesfurther along the desired path, all working as a carrot moving ahead ofa running rabbit. Of course that the reverse action can be also created,of a same sign charge being introduced behind the moving current, inwhich case this same charge charge could be seen as akin to a whip atthe back of the moving current, a horse-type incentive added to arabbit-type one.

Two and three electrodes heart pacemakers are becoming common nowadays,and more electrodes may be used if a good reason for them is discovered,as our invention does. Even three anchored heart cordums in threedifferent places already open new possibilities for shaping the electricfield; more than three offer even more possibilities.

DESCRIPTION AND OPERATION OF ALTERNATIVE EMBODIMENTS

Another embodiment of our invention is application to DBS (Deep BrainStimulation). In this application the objective is to disrupt theanomalous neurons firings that cause the tremor characteristic ofParkinson's disease, or of what is known as essential tremor. One of thepossible solutions is to place an electrode on a chosen target area inthe brain then superimpose a current of frequency around 200 Hz on it.FIG. 12 shows a brain-type stimulator we call picafina, similar instructure to prior art stimulators with 4 rings at their distalextremity (Butson and McIntyre (2006)) but with the equivalent electrodedescribed for the heart cordum: active and passive (field-shaping)electrodes. The objective for the Deep Brain Stimulator (DBS) is toadjust the electric field in the vicinity of the brain electricstimulator, which we call picafina or picafina-style stimulator, to theshape of the particular target volume, which could be the sub-thalamicnucleus (STN), the globus pallidus internus (GPi) or any other. Mucheffort has been put on the solution of this problem, the solution ofwhich has evaded the practitioners of the art for decades—see, forexample, Butson and McIntyre (2006). It can be seen at Butson andMcIntyre (2006) that the best solution proposed is still a symmetricfield. Such a symmetric field fail to offer a maximum electricalstimulation in any case, particularly when the electric stimulatorhappens to have been implanted off-center. As discussed by Butson andMcIntyre (2006), this is, in fact, a most common occurrence, due to thesmall size of the target volumes and their location deep in the base ofthe brain (for DBS), which is also not directly observed by the surgeon,which inserts the electric stimulator through a one-cm diameter holedrilled at the top of the skull, from where she tries to guide thestimulator tip to the desired target volume (but they call it targetarea or simply area for some obscure reason). Our invention allows formore control of the electric field around the stimulator, which in turn,allows for better clinical results. More modern stimulators, e.g. theones introduced by Sapiens Neuro (www.SapiensNeuro.com) and {enterarticle of Hubert Martens reference here} are capable of creating anasymmetric electric charge distribution in the target area, but fail todecouple the control of the electric field from the injection of theelectric charges, therefore failing to maximize the results.

FIG. 13 shows another schematic view of the picafina brain-stylestimulator, though other than the stimulator contour, which reminds theDBS stimulating support picafina, the schematic representation couldtransfer to the heart-type cordum, to the planar type, which in turn maybe flexible as a plane bed sheet, and any other. In it, 110 is ahermetically sealed box, which in prior art is normally made of titaniumor any other bio-compatible material, the energy storage unit BAT1(battery) and the microprocessor MP1 are omitted for simplicity, 124 isthe power (voltage or current) wires, one for each electrode,potentially at different voltage/current levels, 130 the picafinastimulator-type, and 140 the plurality of electrodes, some of which areactive, others are of the field-shaping type, potentially of thesub-surface type, which in this figure are not differentiated betweenactive and field-shaping, for simplicity.

FIG. 14 shows another schematic diagram of a picafina brain-stylestimulator of our invention with the active electrodes 140_t 1 at thesurface of the supporting structure and the sub-surface field-shapingelectrodes 140_t 2, underneath the active electrodes 140_t 1. FIG. 14displays a cut-away view of a picafina with electrodes inside the bodyof the supporting structure. Note also that FIG. 14 omits displayingelectrodes on the side of the viewer, for difficulty of making such adrawing, and on the back side, for a similar reason and also for beinginvisible on the back side. FIG. 14 is a schematic representation, not areal rendition with all details, showing a cut-away view, the cut madeby a plane containing the axis along the long dimension of the picafinaand parallel to the viewer. The same principles are applied to thecordum heart-type stimulator and to other variations of it.

The electrodes for DBS can be of different size, of different shapes andalso randomly distributed on the surface of the supporting structure orpicafina, or they can be of uniform size and shape, perhaps to decreasemanufacturing cost, for example, or to simplify the internal wiring, orany other reason. Given the small size of the electrodes, random shapeof them is of smaller effect than their numbers, while the use of thetwo types of electrodes, active or type-1 electrodes and passive ortype-2 electrodes are of major importance, given that the latter onlychange the electric field shape around the stimulator device.

The reader will notice that the DBS application is a natural adaptationof all that is described for the cordum heart pacemaker, yet the DBSneeds no time control of a sequential muscular contraction, so it issimpler to program and to use than the heart cordum. A multiplicity ofelectrodes, of variable shapes and sizes, each associated with a uniquewire, which is used to select which electrode is turned on, whichelectrode is turned off, both for type-1 (active) and type-2(field-shaping). Likewise for the cordum heart pacemaker, the DBSincarnation uses two types of electrodes: a first type, 140_t 1 oractive type, capable of injecting a current, and a second type, 140_t 2or field-shaping type, which is insulated, not capable of injecting anycurrent (though always there is a small leak current due to insulatorimperfections), but which is much useful for creating the vector fieldaround the electrode, which, in turn, determine the 3-dimensional pathfor the injected current.

Another possible application for the invention is for appetite control.In this application there are two possibilities: electrical stimulationon the stomach, and brain stimulation at the locations which are knownto control the appetite. In the former case the added electricalstimulation may be turned on before a meal, and the electrodes areselected to affect the neurons that send information to the brainregarding the current amount of food in the stomach, which in turnmodulate the appetite. If the stimulation is capable to fool the brain,the individual will feel a decreased urge for food, eat less, and loseweight on the long run. This has been used in humans already. The secondcase, brain stimulation to control the appetite has been only used inanimals so far, and with success. For stomach stimulation the shape ofthe stimulator should be a flat deformable shape (as in a bed sheet) toconform to the curvature of the stomach and its enervations. For directbrain control it may be similar to the DBS.

Another possible application is for cortical brain stimulation, in whichcase the stimulator has a flat shape to adjust to the corticalapplication.

Another possible application is for pain control, an improvement of aknown device known as TENS (Transcutaneous Electrical NeuralStimulation). In this application the objective is to controlsuperficial pain, as skin pain, and it has used for deeper pain too, asmuscle pain. The area (here it is really an area, the surface area ofthe skin in question, not what the neurologists call area, which is avolume) in question is in this case surrounded by electrodes attached tothe skin, from which there is a current flow. Old art used largeelectrodes, which did not allow for a control of the current path. Inthis case our invention discloses a large number of small electrodeswhich are on the surface of the applied patch. Likewise the cordum heartpacemaker, these small electrodes are numbered and individuallyactivated by their dedicated wires which is under control of thecontrolling electronics, are of two types (type-1, or active, andtype-2, or field-shaping), and can likewise be turned on at any of aplurality of voltages/currents or off (zero voltage/current). With awise selection of the active electrodes, it is possible for the medicalpractitioner to ameliorate the pain felt by the patient in a moreeffective way than currently used TENS devices.

Another possible application is for cochlear implants. The problem ofcochlear implants is that the electric charges (the electricalstimulation) originating from a particular electrode spreads out as itpropagates to the neurons in front of it, with the consequence that theelectric charge stimulates the intended neuron and also nearby neurons.For this application what is need is an electric field that forces theartificial electrical stimulation to propagate inside a well-confinedline (in reality a small cylinder) from the electrode to the intendedneuron in front of it. In such a case a set of electrodes behind theactive electrode could cause a force field that cajoles the ions topropagate forward toward the intended neuron. For example, a circularpassive electrode 140_t 2 with center behind the active electrode wouldcreate such a desirable electric field that keeps the ions propagatingforward.

The individual electrodes, which in the main embodiment are randomlyspread on the supporting structure (picafina), and are of various shapesand sizes, can be all of the same shape and/or same size, and/or can bearranged on an orderly arrangement too. In such a case the advantage ofmaximal symmetry breaking is not achieved, but some partial symmetrybreaking is still obtained with the selection of particular electrodesas the points from which to initiate the stimulation, and the selectionof other particular (insulated) electrodes from which to originate thefield shaping lines. Cost and other factors could determine a simplerregular electrode arrangement. More orderly arrangements of theelectrodes than the arrangement disclosed in the main embodiment, whichprovides maximal advantage, are still in the scope of the invention.

Persons acquainted with the art of symmetry will recognize that for verysmall electrodes with small spacing between each, there is little gainif compared with larger electrodes of variable shape and sizes, asparticular sets of smaller electrodes can approximately create the shapeof a larger electrode of any arbitrary shape. Cost and programming timemay dictate one type of another of electrode, and their size andplacement, while these variations are still covered in the scope of theinvention.

The relative distribution of the electrodes of type-1 and type-2(current injecting electrodes and electric field shaping electrodes, ormagnitude and direction determining electrodes) is random in the mainembodiment of this invention, with the active 140_t 1 electrodes at thesurface and the field-shaping 140_t 2 electrodes underneath the activeelectrodes, but it is possible to have field-shaping electrodes at thesurface too.

One interesting regular pattern for the electrodes is the hexagonalpattern, which is shown in figure FIG. 15B, and other variations of it,as the octagonal pattern, shown in figure FIG. 15A.

Persons familiar with the art understand that the hexagonal patterndisplayed at figure FIG. 15B is just one of the many possibilities.Triangular arrays square arrays, rectangular arrays, and others arepossible, these being examples of arrays that completely fill the space.But the individual units do not have to even completely fill theavailable space, because maximal asymmetry (maximal lack of symmetry, ormaximal symmetry breaking) is achieved with random distribution ofelectrodes.

CONCLUSION, RAMIFICATIONS, AND SCOPE OF INVENTION

Another way to see the control of the paths of the current in the heart,or the extent of electrical stimulation in brain DBS, etc., is to lookat the active electrodes determining the magnitude (and also thedirection in a limited way too, because the active electrodes alsocontribute to the electric field vector) and the field-shapingelectrodes determining the direction and speed only of the currentinjected by the former, active electrodes. In this view one considersthe stimulating current as a vector which follows the electric fieldlines.

Other options are possible for the marker 140-tm that indicates theangular position of the cordum as implanted. For example, all theelectrodes may have enough X-ray opacity to show in the fluoroscopicimages taken during the heart pacemaker implantation. Or one or more orthe anchoring arms 131 may be smaller (or larger), or each anchoring armmay be of a different length and/or diameter, to allow theiridentification.

The main embodiment for heart stimulation uses a simple version ofstimulation, which is fixed and continuous, of the type of the old heartpacemakers. It is possible to have stimulation on demand too, as manycurrent pacemakers have, which is based, for example, on activating thestimulation only when the natural pacemaker becomes insufficient, orstops, or becomes erratic. This is called stimulation on demand, easilyincorporated in our invention that already contains a microprocessorcapable of implementing such decisions. Such extensions are part of thecurrent art of heart pacemakers and may or may not be incorporated inour invention. Our invention is independent of stimulation on demand.

One skilled in the relevant art, however, will readily recognize thatthe invention can be practiced without one or more of the specificdetails, or with other methods, etc. In other instances, well knownstructures or operations are not shown in detail to avoid obscuring thefeatures of the invention. For example, the details of the wiring can berealized in several different ways, as coiled wires, as printed circuitwires, etc., many or most of which are compatible with the invention,and therefore the details of these, and other details are not includedin this patent disclosure.

REFERENCES

-   (1) LizhiXu, . . . Igor R. Efimov et al. “3D multifunctional    intergumentary membranes for spatiotemporal cardiac measurements and    stimulation across the entire epicardium” Nature Comm Vol 5 Pg 3329    (March 2014).-   (2) Colleen Clancy and Yang Xiang “Wrapped around the heart” Nature    Vol 507 pg 43 (6 Mar. 2014).-   (3) Pierre Martin “Une membrane artificielle pour surveiller le    coeur” La Recherche (1 Mai 2014).

1. A device for controlling an electrical stimulation of a target areaor a target volume of an animal, comprising: a. an electric stimulatingassist system comprising: a body, an electric energy storage unit, acontrol unit, and a supporting structure configured to be anchored inthe vicinity of the the target area or the target volume, b. thesupporting structure capable of keeping in fixed position a minimum ofone field shaping electrode electrically coupled to the energy storageunit and to the control unit, wherein each of the minimum of onefield-shaping electrodes with a volume and a surface, below the surfaceor at the surface of the electric stimulating assist system, theelectric stimulating assist system connected electrically with wires tothe electric energy storage unit configured to produce a requiredelectric potential at the minimum of one field-shaping electrodeslocated at the electric stimulating assist system, wherein the surfacesof the minimum of one field-shaping electrodes are covered by anelectrically insulating layer which prevents electric charges frommoving out of any of the minimum of one field-shaping electrodes,wherein the minimum of one field-shaping electrodes are adapted toproject an electric field in the space surrounding the electricstimulating assist system, wherein the electric field projected by theminimum of one field-shaping electrodes is configured to apply a forceon the propagating electric charges in the space surrounding the body ofthe electric stimulating assist system, guiding the propagating electriccharges on a target path and/or to keep the propagating electric chargesinside a target volume.
 2. The device of claim 1 further comprisingadditional minimum of one field-shaping electrodes located under thesurface and/or at the surface of the wires that connect the electricenergy storage unit to the electric stimulating assist system.
 3. Thedevice of claim 1 further comprising additional minimum of onefield-shaping electrodes coupled to a skin of an animal in which theelectric stimulating assist system is implanted.
 4. The device of claim1 wherein the supporting structure configured to be anchored in thevicinity of the target area or the target volume wraps around the targetarea or the target volume of the animal.
 5. The device of claim 4wherein the supporting structure configured to be anchored in thevicinity of the target area or the target volume, wrapping around thetarget area or the target volume of the animal covers more than 50% ofthe surface of the target area or the target volume of the animal. 6.The device of claim 4 wherein the supporting structure configured to beanchored in the vicinity of the target area or the target volume,wrapping around the target area or the target volume of the animalcovers more than 1% of the surface of the target area or the targetvolume of the animal.
 7. The device of claim 4 wherein the supportingstructure configured to be anchored in the vicinity of the target areaor the target volume wrapping around the target area or the targetvolume of the animal wraps around the chest of the animal.
 8. The deviceof claim 4 wherein the supporting structure configured to be anchored inthe vicinity of the target area or the target volume wrapping around thetarget area or the target volume of the animal wraps around the head ofthe animal.
 9. The device of claim 4 wherein the supporting structureconfigured to be anchored in the vicinity of the target area or thetarget volume wrapping around the target area or the target volume ofthe animal wraps around the brain or part of the brain of the animal.10. The device of claim 4 wherein the supporting structure configured tobe anchored in the vicinity of the target area or the target volumewrapping around the target area or the target volume of the animal wrapsaround the heart of the animal.
 11. A method of an electrical device ofclaim 1, the method comprising: providing the electrical device of claim1, wherein field shaping electrodes of an electric stimulating assistsystem are configured to apply a force on either the propagatingelectric charges injected in an animal by the electric stimulationsystem, or electric charges naturally produced by the animal.
 12. Themethod of claim 11 further comprising additional minimum of onefield-shaping electrodes located under the surface and/or at the surfaceof the wires that connect the electric energy storage unit to theelectric stimulating assist system.
 13. The method of claim 11 furthercomprising additional minimum of one field-shaping electrodes coupled toa skin of the animal in which the electric stimulating assist system isimplanted.
 14. The method of claim 11 wherein the supporting structureconfigured to be anchored in the vicinity of the target area or thetarget volume wraps around the target area or the target volume of theanimal.
 15. The method of claim 14 wherein the supporting structureconfigured to be anchored in the vicinity of the target area or thetarget volume wrapping around the target area or the target volume ofthe animal wraps around the chest of the animal.
 16. The method of claim14 wherein the supporting structure configured to be anchored in thevicinity of the target area or the target volume wrapping around thetarget area or the target volume of the animal wraps around the head ofthe animal.
 17. The method of claim 14 wherein the supporting structureconfigured to be anchored in the vicinity of the target area or thetarget volume wrapping around the target area or the target volume ofthe animal wraps around the brain of the animal.
 18. The method of claim14 wherein the supporting structure configured to be anchored in thevicinity of the target area or the target volume wrapping around thetarget area or the target volume of the animal wraps around the heart ofthe animal.
 19. The method of claim 14 wherein the supporting structureconfigured to be anchored in the vicinity of the target area or thetarget volume wrapping around the target area or the target volume ofthe animal covers more than 10% of the surface of the target area or thetarget volume of the animal.
 20. The method of claim 14 wherein thesupporting structure configured to be anchored in the vicinity of thetarget area or the target volume wrapping around the target area or thetarget volume of the animal covers more than 1% of the surface of thetarget area or the target volume of the animal.